SDSC, NCAR, LLNL, IBM Team Sets US records in weather simulation

Collaborative effort results in new US records for speed, scale, detail and parallelism

A team of researchers from the National Center for Atmospheric Research (NCAR), the San Diego Supercomputer Center (SDSC) at UC San Diego, Lawrence Livermore National Laboratory (LLNL), and IBM Watson Research Center has set U.S. records for size, performance, and fidelity of computer weather simulations, modeling the kind of “virtual weather” that society depends on for accurate weather forecasts.

For the highly detailed weather simulations, the researchers used the sophisticated Weather Research and Forecast (WRF) model, widely used for continuous weather forecasting by government, military, and commercial forecasters as well as for weather and climate research in hundreds of universities and institutions worldwide.

The team's efforts open the way for simulations of greatly enhanced resolution and size, which will serve as a key benchmark for improving both operational forecasts and basic understanding of weather and climate prediction.

The scientific value of the research goes hand-in-hand with the computational achievements. The “non-hydrostatic” WRF weather code is designed for greater realism by including more of the physics of weather and capturing much finer detail than simpler models traditionally used for global scale weather prediction. Running this realistic model using an unprecedented number of computer processors and simulation size enabled researchers to capture key features of the atmosphere never before represented in simulations covering such a large part of the Earth’s atmosphere. This is an important step towards understanding weather predictability at high resolution.

“The scientific challenge we’re addressing is the question in numerical weather prediction of how to take advantage of coming petascale computing power,” said weather scientist Josh Hacker of NCAR. “There are surprisingly complex questions about how to harness the higher resolution offered by petascale systems to best improve the final quality of weather predictions.” Petascale computing refers to next generation supercomputers able to compute at a petaflop (10^15 calculations per second), equivalent to around 200,000 typical laptops.